High Power Density Of Diesel Engine Crankshaft Strength And Fatigue Analysis

In recent years, with the development of industrial technology, the engine power is demanded more and more high, abroad because of the high power density diesel relatively early, its technology has reached a very high level, in contrast, domestic R&D design level is relatively backward. One of the important performance indicators of the thermal power machinery is the power density, especially on the space size requirements are very stringent vehicle, high power density diesel engine is very important.As everyone knows, the engine want to have a higher power, the engine major moving parts of the load bearing capacity demands higher, The force of inertia generated by the high gas pressure and high-speed movement of parts in the crank linkage, according to the moving parts of conventional design can withstand such a high mechanical load, the structural design of the crankshaft have any special requirements.high power density diesel engine main components of stress and fatigue life is our design and research priorities. Owing to high power, part of the strength and fatigue resistance demand is very high, the crankshaft is one of the most important parts of. If the crankshaft strength is not enough will result in bending and distortion, and even rupture; and the other crankshaft fatigue life is not enough, will also cause the premature failure and fracture, thus affecting the normal work of the engine, and even cause safety accident. This paper use the Proe software to build3D model of engine crankshaft, then using finite element analysis software Ansys analysis strength, finally get the high power density of crankshaft stress distribution, and check its strength on the basis of it. In the engineering field, to accurate predict fatigue strength and life of crankshaft was very difficult. Therefore, to car company, to design a practical, reliable accuracy, long fatigue life of the crankshaft, has important significance.As the main research object. The high power density of the crankshaft of the diesel engine, I use Ansys to have dynamic analysis, on the basis of the crankshaft structure optimize, to reduce stress concentration, and fatigue calculation for high power density, the crankshaft design and research provide theoretical help.The main work of this paper can be summarized as follows:1. by constant power and high power diesel engine indicator diagram, dynamic calculation. Comparison of two diesel engine crank shaft load.2. According to the high power density diesel engine indicator diagram and design rules to design of crankshaft3. using finite element analysis software ansys for engine crankshaft model, meshing, and analyze the strength of crankshaft, finally get the stress distribution and its strength check.4. Have a structure optimization and its strength check to high power density of diesel crankshaft.5. Finally, I calculate the crankshaft fatigue strength, according to the Goodman formula, checking fatigue strength of crankshaft.